Portenko, N. I. “A Probabilistic Representation for the Solution of One Problem of Mathematical Physics”. Ukrains’kyi Matematychnyi Zhurnal 52, no. 9 (September 25, 2000): 1272–1282. Accessed April 11, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/4534.